Box forming machines



Sept. 26, 1967 c. .1. GROSS BOX FORMING MACHINES 8 Sheets-Sheet 1 Original Filed May 10, 1963 [HI/en for Charles JGross By his Aim/"n63 Sept. 26, 1967 c. J. GROSS BOX FORMING MACHINES 8 Sheets-Sheet 2 Original Filed May 10, 1963 Sept. 26, 1967 c. J. GROSS 3,343,464

BOX FORMING MACHINES Original Filed May 10, 1963 8 Sheets-Sheet 5 3znI Y 345 a a a 334 o w 3% 322 Sept. 26, 1967 c. J. GROSS BOX FORMING MACHINES 8 Sheets-Sheet 4 Original Filed May 10, 1963 p 1967 c. J. GROSS 3,343,464

BOX FORMING MACHINES Original Filed May 10, 1963 8 Sheets-Sheet 5 Sept. 26, 1967 c. J. GROSS 3,343,464

BOX FORMING MACHINES Original Filed May 10. 1963 8 Sheets-Sheet 6 p 1967 c. J. GROSS I 3,343,464

' BOX FORMING MACHINES Original Filed May 10, 1963 8 Sheets-Sheet 7 p 1967 c. J. GROSS 3,343,464

' BOX FORMING MACHINES Original Filed May 10, 1963 8 Sheets-Sheet 8 United States Patent 3,343,464 BOX FORMING MACHINES Charles J. Gross, Winchester, Mass., assignor to Hpague- Sprague Corporation, Lynn, Mass, a corporation of Massachusetts Original application May 10, 1963, Ser. No. 279,419, now Patent No. 3,237,535, dated Mar. 1, 1966. Divided and this application Jan. 20, 1966, Ser. No. 521,868

3 Claims. (Cl. 93-36) This application is a divisional application of U.S. Ser. No. 279,419, filed May 10, 1963, now Patent No. 3,237,- 535, issued Mar. 1, 1966.

This invention relates generally to devices for applying pressure and more particularly is directed to a mechanism for pressing box ends in a box forming machine.

It is a general object of the invention to provide pressure applying means which minimizes power consuming forces of friction usually inherent in such devices and which render such devices generally inefiicient and subject to excessive wear. To this end, a pressure plate is provided with nut units through which extend threaded shafts. The nut units contain ball bearings which run in the threads to provide a mounting means for substantially friction-free guidance for movement of the pressure plate as Well as to provide a means for causing such movement by rotation of the shafts. Power means are utilized for rotating the shafts to apply pressure and means are also provided to disconnect the power means to permit manual rotation of the shafts for adjusting the spacing between the pressure plate and an anvil or form.

In the embodiment of the invention described herein, there are two pressure plates on opposite sides of a form over which is wrapped the ends of a box of paperboard or the like. Both pressure plates are mounted on shafts having threads of opposite hands at opposite ends of the shafts enabling simultaneous pressure application by both plates against the form. While the pressing mechanism is described herein as applicable to a box forming machine, it should be apparent that the devices used have universal application wherever it is desired to apply pressing forces with a minimum of frictional loss.

The above and other features of the invention together with various novel details of construction and combinations of parts will now be described with particular reference to the accompanying drawings and thereafter pointed out in the claims.

In the drawings:

FIG. 1 is a perspective view of the entire machine embodying the present invention;

FIG. 2 is a diagrammatic view showing the condition of the box blank as it is fed progressively through the machine;

FIG. 3 is a side elevation of the box forming station with parts broken away;

FIG. 4 is a plan view of the box forming station;

FIG. 5 is a section substantially on line VV of FIG. 4;

FIG. 6 is a section on line VI-VI of FIG. 4;

FIG. 7 is a perspective view of one end of the box forming station with the parts shown in the box forming positions;

FIG. 8 is a section substantially on line VIII-VIII of FIG. 3; and

FIG. 9 is a section substantially on line IX-IX of FIG. 8.

A typical machine in which the invention may be embodied is shown in FIG. 1 and includes a magazine 30 for holding a stack of box blanks to be formed into boxes, a blank separating device 32 for transferring one blank at a time from the bottom of the magazine to a corner lap bending station 34, a station 36 for applying adhesive Patented Sept. 26, 1967 to the end wings of the box, an end win-g extension bending station 38 and a box forming station 40.

FIG. 2 illustrates the various folded conditions of the box blank 10 as it is fed through the various operating stations of the machine. In its initial flat condition the blank 10 comprises a rectangular bottom portion 11 from which project opposite side wings 12 and end wings 16, the side wings and the end wings being connected to the bottom portion along prescored fold lines. The opposite ends of the side wings have corner laps 14 foldably connected thereto while the end wings are provided with foldable extension 18. The condition of the box blank is shown as fiat as it is fed from the magazine to the station 34 where the corner laps 14 are folded down over a pair of guide rails which extend through the machine to the forming station 40. The blank is then fed along the rails through the station 36 where adhesive is applied to the undersides of the end wings 16 and thereafter through the unit 38 which flexes the end wing extensions 18. Finally the blank is fed into the forming station 40 where the side wings and the end wings are down folded and the end wing extensions 18 are infolded over the combined corner laps 14 and end wings 16. After the blank is folded in this manner, pressure is applied to the folded ends to complete the forming of a box 20. For a more complete description of each station, reference may be had to said application Ser. No. 279,419.

After passing through the various stations, the blank is fed from the station 38 over a forming plate 230 (FIGS. 3-6) at the forming station 40. The plate has a rectangular outline substantially corresponding to the bottom portion 11 of the blank and is secured to the upper end of a rod 232. The rod is guided for heightwise sliding movement normal to the upper surface of the plate in a bore 234 formed in a rod 236 which in turn is guided for coaxial heightwise sliding movement in a bearing 238 secured to the machine frame. At its lower end the rod 232 is connected by a link 240 (FIG. 3) to a cam lever 242 pivotally mounted on a shaft 246 journaled in a bracket 106. For raising and lowering the plate 230 during its box forming movement the lever 242 is provided with a cam roll 248 adapted to engage a cam 243 fixed on a cam shaft 50. During the upward movement of the forming plate 230 the bottom portion 11 of the blank is moved up between four rails 260, 261 spaced apart at opposite sides of the forming plate a distance corresponding to the width of the bottom of the blank where the side wings 12 are connected. At the lower ends of the rails there are formed curved surfaces 272 (FIG. 6) adapted to be engaged by the side wings 12 of the box blank as it is moved upwardly by the plate 230 to commence the down folding movement of the side wings. As the plate 230 continues its upward movement the end wings 16 of the blank engage and are folded down by the lower edges of a pair of pressure plates 290 as best seen in FIG. 7. Further movement of the plate 230 raises the box blank to a position entirely between the pressure plates 290 where the side wings and end wings are fully folded. As soon as the forming plate 230 has reached its uppermost position a main box form 300 which conforms substantially to the shape and size of the interior of the box is adapted to be moved heightwise following the direction of movement of the forming plate 230. To this end the form 300 is fixed to the upper end of the rod 236 which at its lower end is connected by links 302 (FIG. 3) to a cam lever 304 also pivoted on the shaft 246 and adapted to be oscillated by a cam 305 fixed on the cam shaft 50. As the form 300 is raised it engages the inwardly bent extensions 18 on the end wings 16 and folds them upwardly over the inturned corner laps 14. In the final position of the form 300 the folded blank is substantially supported by the form from the inside and between the pressure plates 290.

At this point in the machine cycle the pressure plates 290 are moved inwardly to press both ends of the folded blank against the opposite ends of the form 300 so that the formed box ends become adhesively secured. To this end, each of the pressure plates has secured thereto a pair of ball nut units 320 (FIGS. 4 and 5) threadably receiving a pair of screw shafts 321, 322 which extend across the .machine and are journaled in bearings 324 fixed in upstanding end plates 326 secured to the machine frame. At opposite ends, each of the screw shafts 321, 322 is provided with threads of opposite hand in which run balls 323 (FIG. 4) in the nut units so that simultaneous rotation of the shafts cause the pressure plates 290 to be moved toward or away from each other depending on the direction of rotation of the shafts. So that the screw shafts 321, 322 are rotated in synchronism they are provided with sprockets 330, 332 (FIG. 3) over which runs a chain 334. To maintain the chain under tension, an adjustable sprocket 336 is provided. At one end, the ball screw 322 has adjustably secured thereto an arm 340 which is connected by a yieldable link 342 to a cam lever 344 mounted for swinging movement on a shaft 346 journaled in the bracket 106. The cam lever 344 is in the form of a bell crank and the other arm thereof carries a roll which rides on a cam 347 fixed to the cam shaft 50. The yieldable link 342 comprises a body portion 350 which is connected to the arm 340 and a rod 352 which is connected to the cam lever 344. The rod 352 has an enlarged head 354 which engages the upper end of a spring 356 on the rod, the lower end of the spring being contained by a shoulder in the body portion 350. Since the ball screws 321, 322 are rotated to apply pressure to the box ends upon downward movement of the cam lever 344 it may be seen that upon solid engagement of the pressure plates 290 with the ends of the box further downward movement of the cam lever 344 acts to compress the spring 356 so that only a predetermined pressure will be applied to the box ends.

So that the machine may be adapted for forming a wide variety of box sizes and shapes, provision is made for adjusting the spacing between the pressure plates 290' to accommodate different sizes of box forms. To this end, the arm 340 is adapted to be disconnected from the screw shaft 322 so both screw shafts may be simultaneously rotated by hand. For this purpose both shafts are provided with squared ends to receive a handle (not shown). As best seen in FIGS. 8 and 9 the sprocket 332 has fixed thereto a plate 358 having semi-circular depressions 359 equally spaced about its circumference. The portion of the arm 340 adjacent the plate 358 carries two rotatable pins 360 having knobs 361 (see also FIG. 3) and semicylindrical ends 362 adapted in one rotatable position to be received in driving engagement with one of the depressions 359 and in the other rotatable position to be disengaged and in non-driving position outside the circumference of the plate 358. As seen in FIG. 9 one of the pins is in driving position so the arm 340 is connected to the shaft 322. By rotating the engaged pin 180, the arm is easily disconnected to permit manual rotation of the shaft to adjust the spacing between the pressure plates 290. The spacing between the pins 360 is such that only one pin may be engaged at a time with the other pin positioned between two depressions 359. This permits a fine adjustment of the relative positions of the arm 340 and sprocket 332.

From the foregoing description, it should be apparent that the unique principles involved in the pressure applying mechanism of the forming station are also useful in other types of machines without departing from the scope of the invention.

Having thus described my invention, what I claim as novel and desire to secure by Letters Patent of the United States is:

1. In a machine for forming boxes from blanks of sheet material, a forming station including a form having a shape corresponding generally to the interior of a finished b0x,'at least one pressure plate at one end of said form, means mounting said plate for movement toward and away from said form for applying pressure to the end of a blank folded over the form, said mounting means comprising a pair of shafts each having screw threads thereon and fixed against axial movement with respect to the form, a pair of nut units fixed to said plate and through which extend the threaded portions of said shafts, each of said units having ball bearings running in the threads of said screws for mounting the plate on the shafts for substantially friction-free movement of said plate with respect to said form and for causing said movement by rotation of said shafts, and means for rotating said shafts simultaneously for moving the pressure plate toward and away from said form.

2. A box forming machine as described in claim 1 having means for disconnecting the rotating means from the shafts whereby said shafts are manually rotatable to vary the operating position of the plate on the shafts.

3. A box forming machine as described in claim 1 in which pressure plates are mounted on the shafts at opposite ends of the form, each shaft having threads of opposite hand mounting the plates whereby rotation of the shafts causes simultaneous movement of the plates toward and away from the form and means are provided to disconnect the rotating means from said shafts whereby the shafts are manually rotatable independently of the rotating means for varying the spacing between said pressure plates to accommodate boxes of differing sizes.

References Cited UNITED STATES PATENTS 541,953 6/1895 Taylor 93.-51 1,972,359 9/1934 Schenck 74625 X 2,023,579 12/1935 Dodge 74582 X 3,053,105 9/1962 Cole 74428.8

BERNARD STICKNEY, Primary Examiner. 

1. IN A MACHINE FOR FORMING BOXES FROM BLANKS OF SHEET MATERIAL, A FORMING STATION INCLUDING A FORM HAVING A SHAPE CORRESPONDING GENERALLY TO THE INTERIOR OF A FINISHED BOX, AT LEAST ONE PRESSURE PLATE AT ONE END OF SAID FORM, MEANS MOUNTING SAID PLATE FOR MOVEMENT TOWARD AND AWAY FROM SAID FORM FOR APPLYING PRESSURE TO THE END OF A BLANK FOLDED OVER THE FORM, SAID MOUNTING MEANS COMPRISING A PAIR OF SHAFTS EACH HAVING SCREW THREADS THEREON AND FIXED AGAINST AXIAL MOVEMENT WITH RESPECT TO THE FORM, A PAIR OF NUT UNITS FIXED TO SAID PLATE AND THROUGH WHICH EXTEND THE THREADED PORTIONS OF SAID SHAFTS, EACH OF SAID UNITS HAVING BALL BEARINGS RUNNING IN THE THREADS OF SAID SCREWS FOR MOUNTING THE PLATE ON THE SHAFTS FOR SUBSTANTIALLY FRICTION-FREE MOVEMENT OF SAID PLATE WITH 